This invention relates to an electronic control system for use with a weight measuring scale. In particular, the electronic control system of the present invention is designed for use with a pneumatic scale of the type described in U.S. Pat. No. 2,704,197 (Howard).
Pneumatic scales of this type have been widely used because of their accuracy and reliability, particularly in the packaging of cereals. The precise accuracy of the pneumatic scale results from a large weight-to-scale deflection factor, since all scale movement occurs only at and around the label weight of the box. The buoyancy created by the air suspension of the scale isolates the scale from environmental and machine vibrations.
A problem frequently encountered with the pneumatic scales, especially in the cereal box filling application, is the build-up of residue inside the scale. For example, sugar on sugar-coated cereals will often stick to the scale after the product has been released into the box. This residue creates inaccuracies in the measuring process.
Furthermore, it was difficult to evaluate the operation of pneumatic scales of the prior art since no numerical output was produced or stored for statistical analysis.